Safety device for boilers.



D. LDUGGAN.

SAFETY DEVICE FOR BOILERS.

APPLICATION FILEDAFR. 21| 1915.

Patented Nov. 20, 1917.

WITN ESSES www@ n @WW l QVM Mv/yf a QMGWPWM GHR stri-rains rafrnrrr onirica DANIEL JAMES .'DUGGAN, OF EVERETT, VTASEINGTON, ASSIGNUR 0F ONE-HALF T0 SYLVESTERQROPER, 0F LOWELL, TiASI-INGTON.

SAFETY DEUCE FOR BOILERS.

reinem.

Application filed April 27, 1915.

To all trimm it may concern Be it known that l, DANIEL J. DUGGAN, of Everett, Snohomish county, Washington, have invented a new and useful Safety Device for Boilers, ofivhich the following is a full, clear, and exact description; reference being` had to the accompanying drawings, forming part of this specification, in Which:-

Figure l is a transverse section through one type of boiler showing one type of my improved safety device connected thereto.

Fig. 2 is a longitudinal section through another type of boiler showing a modified form of my improved safety device; and

Fig. 3` is a detailed ligure of another modified form. i

This invention relates to safety devices which are arranged to control the consumption of fuel when the Water in the boiler passes the danger line, or the pressure of the steam rises above a predetermined limit.

rlhe object of my invention is to provide a device in which the lire under the boiler' in the combustion chamber Will be quenched or extinguished when the Water in the boiler passes below a certain level or the steam pressure exceeds a predetermined limit. If solid fuel is used in the combustion chamber it is deadened by means of steam or water; or e combination of steam and Water, the admission ef which .is automatically controlled by the level of the Water in the boiler or the steam pressure; and if liquid or `gaseous fuel is used the supply thereof is automaticallyT cut olf by an automatic device when the water in the boiler reaches a predetermined lon7 level or by excess steam pressure.

'.lhe precise nature of my invention will be best understood by reference to the accompanying drawings7 it being premised, howeveny that various changes may be made in the details of construction and arrangement of the various parts, Without departing from the spirit and scope of my invention as defined in the appended claims.

In Fie. l of the drawings, the numeral 2 designates the boiler of the fire tube type having lire tubes 3 extending therethrough. Placed at any convenient point is a Water column 4, the upper end of which is connected to the steam space of the boiler bv means of a pipe 5, While the lower end thereoi is connected to the Water space by means Speccaton of Letters Patent.

lllatented N ov. 23th, iililf?.

Serial No. 24,219.

of a pipe (i. Extending from the lower portion of the column #t to a point Within the furnace is a pipe i' having a valve 8, which is arranged to be opened and closed7 as hereinafter described, to permit water to pass from the boiler through the pipe when the valve is opened. The stem of the valve S is connected to a diaphragm in a chamber 9 which is connected by means of a pipe l0 with a bushing 1l in the upper portion of the column -i-. The lovvci face of the bushing li provided with a valve seat for a needle valve l2 on the upper end of the stem 13 connected to a float lil Within the column 4.

1When the Wat-er Within the boiler 2 is above the normal water level i? the iioat will be held in its elevated position so that the needle valve l2 will be seated against the Linder side of the bushing 1l and thereby prevent any steam from passing through the pipe l0 to the diaphragm chamber to open tbe valve S. :if for any reason the Water should fall below the normal Water level L as indicated in Fig. l, the float 1i will fall and permit steam to pass from 'the steam space of the boiler through the pipe 5, column ei and pipe iO' to the diaphragm chamber 9, and open the valve 8 to permit water to floiv from the boiler through the pipe 7 to quench the i'ire.

After the lire has been quenched and su'llicient water has again been pumped into the boiler to bring` the level above the danger point, the float 'lei will be raised and shut off the connection to the pipe l0. After this connection has been closed the pressur in the pipe can be reduced by opening the relief valve 15.

Connected to the pipe 5 and the pipe l0, is a pipe 1G for permitting steam to pass directly from the boiler to the diaphragm chamber 9 to open the valve 8, and 17 is a pop valve in the pipe 16 which is set to permit the steam to pass directly to the chamber 9, when the steam pressure in the aoiler reaches a predetermined limit. If, for any reason, the pressure in the boiler should rise above the safety limit, the valve 17 will be opened and the steam will act directly on the diaphragm in the chamber 9, and open the valve 8 to permit Water to dow through the pipe 7 to quench the lire.

In Fig. 2 l have shown an arrangement which is somewhat similar to that shown in Fig. l and in which I have applied the same reference characters to similar parts with the letter a aliixed.

In this figure l have illustrated a locomotive boiler, and instead of connecting the pipe 7a with the Water space of the boiler through the medium of the column 4a, l connect the pipe either with an external source of Water pressure, or the steam space of the boiler, so that when the valve 8a is opened water or steam will be admitted through the pipe 7 to quench the tire in the combustion chamber.A

In F ig. 3 I have shown still another modified form in which the one end of pipe 7b can be connected to the liquid 0r gaseous fuel supply, While the other end of said pipe is connected to a burner Within the furnace. In this construction the valve 8b is arranged to be closed by meansof the-diaphragm Within the diaphragm chamber 9b, so that the fuel supply will be entirely cut off when the Water in the boiler falls below a predetermined level.

The advantages of my invention result from the provision of means for automaticallyV controlling the fire Within the combustion chamber of the boiler when the Water in the boiler falls below a predetermined level or the pressure therein rises above a predetermined point.

I claim:

l. A safety device for boilers, comprising means for controlling the consumption of fuel. under the boiler, a device adapted to be boiler for actuating said means, and a second device actuated by excess pressure in the boiler for actuating said controlling means irrespective of the levelof the Water in the boiler, substantially as described.

E2. A safety device of the character de scribed, comprising means for controlling the consumption of fuel in a boiler furnace,

a float chamber extending above and below the normal Water level ofthe boiler, a float Within said chamber, there being Water and steam connections between said fioat Chamber and the boiler, apipe leading to the furnace chamber of the boiler, a valve in said pipe, a diaphragm chamber, a diaphragm in said chamber, actuating connections between DANIEL JAMES DUGGAN.

i Witnesses:y

E. J. COLLINS, E. D. BAKER.

Copies of this patent may be obtained for ve cents each. by addressing the Commissioner of Patents Washington, D. C. f i

` controlled by the level of the Water in the 

